Double Back Beam: Weave with two tensions

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Our floor looms (except the Wolf Pup and Wolf Pup LT) can be fitted with a double back beam. A double back beam is a second beam that is attached behind the first beam and has a separate brake drum and brake release.
The main purpose of using two beams is so that two warps can be separately tensioned. Why would you want to do this? Well, let’s say that you want to weave a double weave fabric where one layer weaves longer than the other, for example to weave pleats. In order to do this easily, you need to beam one layer on one beam and the other on the other beam. That way, when you weave one layer you do not affect the layer on the other beam. (In this example, you will also need to figure add extra warp length for the pleats.)
You might choose to use two beams if you are weaving a plain weave ground and a supplementary pattern warp (think turned overshot). In this case, the ground threads would be threaded on one beam and the pattern threads on the other beam. You need two beams with separate tensions because the ground warp will have more take-up because it interlaces more often than the pattern warp which interlaces only at intervals (and therefore will not take-up as much as the ground warp). This matters because over the length of the warp, the pattern threads will become looser and looser, causing tension headaches that can easily be avoided by using a second beam.
Tips for threading two beams:
• Measure two separate warps, one for each beam.
• You’ll need two sets of lease sticks.
• Use the back to front warping method.
• Start with the second beam first: spread the warp in a raddle, wind onto the beam.
• Wind the second warp on your original beam in the same manner.
• Suspend the two warps on lease sticks hung on the back of the castle, hanging the two leases at different heights will make it easier to see both sets of threads.
• Follow the threading draft, choosing the appropriate threads from the two sets of lease sticks.
Turning a draft in brief
You can turn a draft 90 degrees for the same woven appearance. To do this, the threading becomes the treadling, the treadling becomes the threading, and the tie-up is used sideways. For example, if you turn an overshot draft, you will thread the pattern and the background threads in the warp and just weave with background threads in the weft. This means that weaving proceeds quicker because just one shuttle is used. Be sure to include the tabby picks in the treadling when you turn the draft for the threading.